<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>变量</title>
</head>
<body>

</body>
<script>
    /*局部变量和全局变量*/
    {let b = "aaa";
    i = "bbb";}
    document.write(i);

    document.write("<br>");

    /*常量*/
    const c = 123;

    document.write(c)
</script>
</html>